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发布时间:2010年08月07日,  已有 4 人推荐

来源Photos: Algae Blankets China Beaches; Dead Zone Brewing?

Photos: Algae Blankets China Beaches; Dead Zone Brewing?



Green Tide


A child plays on an algae-matted beach in the coastal city of Qingdao (map) in east China’s Shandong Province earlier this month.


Local authorities and residents in the popular tourist destination have been struggling over the summer to remove a large mass of green algae that has washed ashore. As of late June, the algae bloom—or “green tide”—covered more than 170 square miles (440 square kilometers) of coasts south of Qingdao.


The algae blanketing the city’s beaches belongs to a species of marine plankton known as Enteromorpha prolifera. The algae can be found in waters all around the world, and can explode in so-called macro-algal blooms if conditions are right, said Steve Morton, a marine biologist at the National Oceanic and Atmospheric Administration (NOAA).

国家海洋与大气治理署的海洋生物学家史蒂夫.莫顿说, 覆盖青岛海滩的水藻属于一种叫做浒苔的海洋浮游生物。全世界的水域中都有水藻,条件成熟便会大规模爆发,形成所谓的藻华。

Such massive blooms require warm ocean temperatures and waters rich in the elements phosphorus and nitrogen, which are found in fertilizers and can be carried to the coasts by water runoff. While the algae isn’t toxic, big blooms can create oxygen-poor “dead zones” in the water and leave an unpleasant odor on beaches.



Weeding the Beaches


A man clears algae by the armful from a beach in the coastal city of Lianyungang, about 150 miles (240 kilometers) south of Qingdao, on June 22.


China has had a steady drop in air and water pollution over the past three years, thanks to stringent environmental regulations and the closure of some highly polluting, energy-intensive companies. (Related: “Chinese Air Pollution Deadliest in World, Report Says.” [2007])


But fertilizer runoff from farms to the coasts remains a problem, NOAA’s Morton said: “With its population like it is, [China] has to feed a lot of people, so they use a lot of fertilizer.”



Algae Explosion


Workers remove large mounds of algae from Jinshatan beach on Qingdao’s Yellow Island on July 3.


China is notorious for its algae blooms. During the 2008 Summer Olympics in Beijing, a sailboat race was almost canceled because of an outbreak. “They had thousands of people raking the ocean to get the algae out,” NOAA’s Morton said. “It was an amazing sight.”

中国藻华泛滥早已“臭名远扬”。2008年北京夏季奥运会期间,一场帆船赛差点因为藻华而取消。“中国政府派去数千人清理海藻,” 国家海洋与大气治理署的莫顿说,“场面极其壮观。”

Macro-algal blooms are a uniquely modern problem that emerged after humans learned how to create potent artificial fertilizers in massive amounts, added Wayne Litaker, a research scientist also at NOAA.

国家海洋与大气治理署另外一位研究专家Wayne Litaker表示,藻华是一个特殊的现代问题,是人类大量使用药效强劲的人工化肥造成的。

“In the 1800s people had to use natural fertilizers such as guano,” which is the excrement of birds, bats, and seals, Litaker said. Now that we have artificial fertilizers, “a lot more goes onto the land than ever before.”




Algae Beach Blanket


A Chinese man walks along a Qingdao beach completely blanketed by algae on June 29.


Thick Enteromorpha algae blooms block the small amounts of sunlight that reach deeper-dwelling marine life. And when the algae die, their remains are broken down by fungi and bacteria that suck up oxygen, creating ocean dead zones, Morton explained.


An algal bloom is a feast for the microscopic decomposers, and the dead zones can persist for months as a result.



Algae-fighting Army


Chinese soldiers in shorts and camouflage shirts help clear algae from a beach in Qingdao on June 26.


According to news reports, Chinese authorities have had to recruit thousands of people and dispatch a flotilla of more than 60 ships to combat the green tide.


Algal blooms washed on shore can give off a stench of rotten eggs or worse, NOAA’s Morton said, caused by the release of methane and sulfur as the blooms decompose.

国家海洋与大气治理署的莫顿说, 绿藻被冲上岸边,随着腐烂分解,会释放甲烷与硫磺,致使海滩臭气熏天,比臭鸡蛋还臭。

Blob Born of Pollution


Local villager Jin Jisong displays a mysterious, semitransparent blob on June 25 that was found in Zhudong Lake in east China’s Zhejiang Province, just south of Shanghai.


According to scientist Wei Xiangtai of the Shangyu Aquatic Product Technology Center, the slimy mass is a product of polluted water—a complex glob of anaerobic bacteria covered in structures that produce spores.



Creature From the Black Lagoon


A close-up of the mysterious blob found in Zhudong Lake. According to the Associated Press, the blob melts in bright sunlight.


Bacteria and algae aren’t the only creatures that can benefit from polluted waters: During a recent algae bloom in Narragansett Bay, Rhode Island, residents complained of an infestation of snails that were feeding on the algae, NOAA’s Morton said.

国家海洋与大气治理署的莫顿说, 能在污水中迅速繁殖的不只有细菌与海藻:最近在美国罗得岛纳拉干塞特湾爆发绿潮,当地居民抱怨蜗牛横行,这些蜗牛专以藻类为食。


Green Ooze


A young man holds algae-filled water from a lake in east China’s Anhui Province on June 22. The algae species responsible for this bloom is most likely Microcystis, NOAA’s Morton said.


The Microcystis algae can be found around the world. In 2003, for example, a NASA satellite spotted a green splotch in Lake Erie that turned out to be a Microcystis bloom.


Since China’s current algal blooms are much worse than anything experienced in the U.S., it’s “very likely” they’re also visible from space, Morton said.

莫顿说,这次中国的藻华比美国以往出现过的都要严重, “很有可能”从外太空也能看到。


Algae Diver


A Chinese diver clears away green algae in the coastal waters off Qingdao on June 29.


Although this algae isn’t toxic, NOAA’s Morton recommends that swimmers stay away from the algae-infested waters if possible.


“Anytime you have a discoloration of water, your best bet is not to swim in it,” he said.



From Bloom to Biofuel


British Foreign Secretary David Miliband walks past an array of pipes containing algae during a visit to a clean-energy research center in the city of Langfang, south of Beijing, on March 15. Many companies worldwide are actively researching how to turn algae into biofuel.

315日,北京南部,廊坊市, 英国外交大臣大卫.米利班德访问一家清洁能源研究中心,走过装满海藻的管道架。现在世界很多公司都致力于研究将海藻转变为生物燃料的方法。

“A huge area of research right now is getting exactly the right [algae] species to grow under the right conditions so you can make enough lipids to make oils out of them and have a commercial product,” NOAA’s Morton said. Lipids are a broad group of molecules such as fats and waxes that don’t dissolve in water.


While it’s possible some of the plankton species responsible for China’s algal blooms could be harvested for biofuel, most companies use their own genetically modified species, Morton added.